Such electric motors are composed of a stator having an exciter winding which can be energized in a stator housing and a rotor which is rotatably mounted in the stator and whose rotor movement is utilized as a working movement. The energization of the exciter winding is usually carried out by soldering stranded conductors to the winding ends, which project initially out of the stator housing and which can be connected to connecting cables. In order to be able to transmit the high currents which are necessary for high motor powers, high-current plug-in connectors, via which the winding ends are connected to a control device of the electric motor, are used for the electrical connection of the electric motor.
However, the currents which are to be transmitted via the plug-in connectors are generally limited to, for example, 80 Amperes so that it is not possible to generate only very high motor powers with this connection technology. On the other hand, it is also not possible to directly connect the motor lines to the control device owing to the comparatively complex mounting.
U.S. Pat. No. 5,514,922 describes an electric motor of the type mentioned at the beginning in which the stator has an exciter winding which can be energized via connecting contacts (“conductor terminals”, see “27a” in FIG. 2 of U.S. Pat. No. 5,514,922), the connecting contacts being specifically connected to the stator housing using an “annular cylindrical projection 113d”, it being possible to connect electrical connection elements (“external conductor leads”, see column 7, line 40) which are axially accessible from the outside to the connecting contacts (“27a”). The connecting contacts are secured by what is referred to as an “isolation base 27”. This construction is therefore very costly and disadvantageous in terms of the mounting of the electric motor.
U.S. Pat. No. 5,861,689 describes an electric motor in which the connecting contacts “terminals 12” (see FIG. 12 in U.S. Pat. No. 5,861,689) are integrated into a connecting plug (“receptacle 10”) which is axially accessible from the outside. This design is also extremely complex to mount.
U.S. Pat. No. 6,132,184 describes an electric motor for the hydraulic pump of a steering gear in which connecting contacts (“tubular contacts 108, 110”, see FIG. 3 in U.S. Pat. No. 6,132,184) and bolt-shaped connection elements (“threaded fasteners 68, 92, 80, 58”) are provided for energizing the electric motor by means of a control device (“control module 16”). The design of the connecting contacts (“tubular contacts”) and of the connection elements is not described more precisely there.
The present invention is based on forming the exciter winding of an electric motor in a structurally simple manner which may permit simple mounting and a high power drain.